The use of dental floss is a well known practice for cleaning food particles from the crevices between teeth to aid in the maintenance of good oral hygiene.
Flossing is accomplished by placing a string of dental floss at the crevice between two teeth and moving the string back and forth to work the dental floss up and down through the crevices. Typically, the string of dental floss is held with one end in each hand of the user and the sting is moved about the inside of the mouth by projecting it into the mouth using the index finger of one or both hands. Using the fingers to move the dental floss about within the mouth is somewhat awkward and has led to the development of various devices for the purposes of assisting in the minipulation of the dental floss. Two such dental flossing instruments are shown in U.S. Pat. Nos. 3,882,879 and 3,908,678.
Whenever such flossing instruments are utilized, it is preferable that there be easy, practical means of creating tension in the string of dental floss and also means for providing advancement (lengthening) of the string.